The FREE Heatmiser WiFi Stat app lets you control your Heatmiser WiFi Thermostat within your home and remotely via a 3G or WiFi connection. Been away and don’t want to arrive back home to a cold house? Tired of hard to use thermostats? Install a Heatmiser WiFi Thermostat and control your heating from our iPhone app. Use our iPhone app within your home and throw away your thermostat manual! Providing your have at least three wires, excluding earth, then you can upgrade your existing thermostat to our DT-TS or PRT-TS WiFi Thermostat. 4 wires are required for our PRTHW-TS WiFi model.